Access ports are widely used in medical procedures to gain access to anatomical cavities ranging in size from the abdomen to small blood vessels, such as veins and arteries, epidural, pleural and subarachnoid spaces, heart ventricles, and spinal and synovial cavities. The use of access ports has become more common as they provide minimally invasive techniques for establishing a portal for a number of procedures, such as those involving the abdominal cavity. Reduced postoperative recovery time, markedly decreased post-operative pain and wound infection, and improved cosmetic outcome are well established benefits of minimally invasive surgery, derived mainly from the ability of surgeons to perform an operation utilizing smaller incisions of the body cavity wall.
In many surgical procedures, it is desirable to provide one or more working channels into a body cavity through which various instruments can be passed to view, engage, and/or treat tissue to achieve a diagnostic or therapeutic effect. In laparoscopic abdominal procedures for example, the abdominal cavity is generally insufflated with CO2 gas to a pressure of around 15 mm Hg. The abdominal wall is pierced and one or more tubular cannulas, each defining a working channel, are inserted into the abdominal cavity. A laparoscopic telescope connected to an operating room monitor can be used to visualize the operative field and can be placed through one of the working channels. Other laparoscopic instruments such as graspers, dissectors, scissors, retractors, etc. can also be placed through one or more of the working channels to facilitate various manipulations by the surgeon and/or surgical assistant(s).
One problem with existing methods and devices is that existing surgical access devices that are configured to receive multiple instruments simultaneously have a very large size, and thus either require large incisions in tissue in order to place the surgical access device, or they cause damage to a smaller incision when the surgical access device is wedged into place. It can thus be difficult to position a large surgical access device in the incision, particularly in minimally invasive surgical procedures where the incision preferably relatively small.
Accordingly, there remains a need for methods and devices for positioning surgical access devices in tissue to form a pathway through the tissue and into a body cavity.